Prevalence of Dry Eye and Its Association with Various Risk Factors in Rural Setup of Western Uttar Pradesh in a Tertiary Care Hospital

Purpose: To study the prevalence of dry eye in a hospital based population of rural setup and to evaluate its association with various risk factors. Material and Methods: In this cross sectional study, patients above 20 years of age were screened randomly for dry eye. An 8 points questionnaires, slit lamp examination of meibomian glands, tear film breakup time, fluorescein staining of cornea, schirmer test were used to diagnose dry eye. The diagnosis was made when three of the five parameters were positive. The role of various occupations as well as role of different exposure factors like sunlight, excessive wind, smoking, drugs, and air pollution as dry eye risk factors was accessed. Result: Out of 445, 45.39% patients had dry eye. Dry eye prevalence was higher in those above 70 years of age (74%). It was higher in male population (51.82%) compare to female population (37.37%), nearly equal in rural (46.04%) and urban population (44.31%) and highest among factory workers (90%). Correlation of dry eye with drugs (P = 0.0002), sunlight/high temperature (P = 0.0003) and smoking (P = 0.03) were significant. Conclusion: This is a hospital based study which provides prevalence of dry eye in rural region of western Uttar Pradesh. It is more common in old age male population and significantly higher in factory workers. Out of different modifiable risk factors most important are drugs, sunlight/high temperature and smoking.

Exploring single atom catalysts of transition-metal doped phosphorus carbide monolayer for HER:A first-principles study

Hydrogen has been identified as one of the most promising sustainable and clean energy. Developing hydrogen evolution reaction(HER) catalyst with high activity is essential for satisfying the future requirements. Considering novel advantages of two-dimensional materials and high catalytic activity of atomic transition metal, in this study, using density functional theory calculation, the HER on single transitionmetal(23 different TM atoms) doped phosphorus carbide monolayer(α-PC) has been investigated. The Volmer–Tafel and Volmer–Heyrovsky reaction mechanisms, and the stability of the most promising HER catalyst are also included. The results show that Ir-αPC with high physical and thermal stability has the most optimal value of Gibbs free adsorption energy for H atom. The relationship of d band center and the HER activity shows a volcano-like curve. The calculation of reaction energy barrier indicates that the Volmer-Heyrovsky step is more favorable than the Volmer-Tafel step.

Structurally ordered high-entropy intermetallic nanoparticles with enhanced C–C bond cleavage for ethanol oxidation

Efficient ethanol oxidation reaction(EOR)is challenging due to the multiple reaction steps required to accomplish full oxidation to CO_(2) in fuel cells.Highentropy materials with the adjustable composition and unique chemical structure provide a large configurational space for designing high-performance electrocatalysts.Herein,a new class of structurally ordered PtRhFeNiCu high-entropy intermetallics(HEIs)is developed as electrocatalyst,which exhibits excellent electrocatalytic activity and CO tolerance for EOR compared to high-entropy alloys(HEAs)comprising of same elements.When the HEIs are used as anode catalysts to be assembled into a high-temperature polybenzimidazole-based direct ethanol fuel cell,the HEIs achieve a high power density of 47.50 mW/cm^(2),which is 2.97 times of Pt/C(16.0mW/cm^(2)).Online gas chromatography measurements show that the developed HEIs have a stronger C–C bond-breaking ability than corresponding HEAs and Pt/C catalysts,which is further verified by density functional theory(DFT)calculations.Moreover,DFT results indicate that HEIs possess higher stability and electrochemical activity for EOR than HEAs.These results demonstrate that the HEIs could provide a new platform to develop highperformance electrocatalysts for broader applications.

调控超细高熵合金晶格应变用于高活性和高稳定性甲醇氧化

高熵合金(HEAs)因其非常规的组成和独特的物理化学性质而得到广泛研究.本文,我们首次提出了一种表面应变策略来调控HEAs的电子结构用于高效的甲醇电氧化反应(MOR).高分辨像差校正扫描透射电子显微镜(STEM)和元素分布分析表明,在Pt Fe CoNi Cu HEAs中各原子分散均匀,并形成FCC晶体结构.700℃热处理所得HEA-700的压缩应变比400℃热处理所得HEA-400的压缩应变高0.94%.正如预期,HEA-700的比活性和质量活性远超HEA-400和目前大多数最先进的催化剂.MOR活性的增强归因于压缩应变导致HEA-700中Pt–Pt键距缩短.同时,核中的非贵金属原子通过转移电子到表面Pt层产生压缩应变和d带中心的下移.这项工作为高性能HEAs电催化剂的设计提供了一个新的视角.

Machine learned interatomic potentials using random features

We present a method to model interatomic interactions such as energy and forces in a computationally efficient way.The proposed model approximates the energy/forces using a linear combination of random features,thereby enabling fast parameter estimation by solving a linear least-squares problem.We discuss how random features based on stationary and non-stationary kernels can be used for energy approximation and provide results for three classes of materials,namely two-dimensional materials,metals and semiconductors.Force and energy predictions made using the proposed method are in close agreement with density functional theory calculations,with training time that is 96%lower than standard kernel models.Molecular Dynamics calculations using random features based interatomic potentials are shown to agree well with experimental and density functional theory values.Phonon frequencies as computed by random features based interatomic potentials are within 0.1%of the density functional theory results.Furthermore,the proposed random features-based potential addresses scalability issues encountered in this class of machine learning problems.